A C++ software library, designed to provide fast and efficient reweighting of large Monte Carlo datasets containing semileptonic b-Hadron decays to any desired New Physics, or to any description of the hadronic matrix elements. See the HAMMER website for more information.
To use the latest HAMMER, you will need:
std::complex<double> literals (See the C++ compiler support status).HAMMER uses CMake to configure the build process. Out-of-source build is required:
~$ tar -xzf Hammer-X.Y.Z-Source.tar.gz
~$ mkdir Hammer-build
~$ cd Hammer-build
~$ cmake -DCMAKE_INSTALL_PREFIX=../Hammer-install <ADDITIONAL_OPTIONS> ../Hammer-X.Y.Z-Source # configure the project. See below for ADDITIONAL_OPTIONS
~$ make # compile the project
~$ ctest -V # runs all the unit tests. Optional, to be called if tests are enabled
~$ make doc # create the code documentation. Optional, to be called if documentation is enabled
~$ make install # install the projectThe following options can be passed to CMake at configure time with the usual -D<OPTION_NAME>=ON|OFF syntax.
| Option | Default | Description |
|---|---|---|
| WITH_PYTHON | ON | Build the HAMMER Python3 bindings |
| WITH_ROOT | OFF | Build the HAMMER ROOT interface |
| WITH_EXAMPLES | OFF | Build the HAMMER examples. The ROOT and Python examples will be built only if the corresponding options are enabled. All the examples will be located in <INSTALL_DIR>/shared/Hammer/Examples after installation |
| WITH_EXAMPLES_EXTRA | OFF | Build HAMMER extra examples. These are longer examples or validation runs which require larger downloads. |
| ENABLE_TESTS | OFF | Build the unit tests |
| BUILD_DOCUMENTATION | OFF | Allows building the doxygen documentation with make doc |
| INSTALL_EXTERNAL_DEPENDENCIES | OFF | Build and install local copies of certain missing dependencies. For missing Python modules a working pip is required |
| FORCE_YAMLCPP_INSTALL | OFF | Install local copy of yaml-cpp even if one is present (rarely needed). Useful on certain systems where package finding and INSTALL_EXTERNAL_DEPENDENCIES both fails |
| FORCE_HEPMC_INSTALL | OFF | Install local copy of HepMC even if one is present (rarely needed). Useful on certain systems where package finding and INSTALL_EXTERNAL_DEPENDENCIES both fails |
| MAX_CXX_STANDARD | 20 | Affects the C++ dialect used by the compiler, to resolve linking issues on certain platforms. The configuration step will choose the minimum of: the maximum dialect supported by the compiler; the value of MAX_CXX_STANDARD; and the dialect used in compiling ROOT if WITH_ROOT option is enabled |
furthermore, the following options are available for debugging
| Option | Default | Description |
|---|---|---|
| VERBOSE_DEBUG | OFF | Build for debugging with high verbosity |
| SANITIZE | OFF | Enable sanitizer infrastructure for debugging (the C++ compiler should have the support enabled) |
| SANITIZE_ADDRESS | OFF | Enable the address sanitizer |
| SANITIZE_UNDEFINED | OFF | Enable the undefined behavior sanitizer |
| SANITIZE_THREAD | OFF | Enable the thread sanitizer |
| SANITIZE_MEMORY | OFF | Enable the memory sanitizer |
and the standard CMake option -DBUILD_SHARED_LIBS=ON|OFF controls whether Hammer is built as a static or dynamic library (static is default) and switching to shared librarary sometimes may be useful for resolving linking issues with the Boost Thread library on some platforms.
The folder Examples/ contains several examples and is a great place to learn to use HAMMER.
| Example | Description |
|---|---|
| demo01 | read MC events, reweighs \(B\rightarrow (D^*\rightarrow D\pi) \tau\nu\) and \(B\rightarrow D \tau \nu\) and from ISGW2 to BLPR for generalized NP, saving all the event NP tensor weights into a file |
| demo02 | read in the output of demo01 and reweighs all the events from Standard Model to new physics with complex Wilson Coefficients \(S_{qLlL} = x i\), \(T_{qLlL}= x/4\) for \(x=0, 0.2, \ldots, 1.0\) printing the values of the first few weights in each case |
| demo03 | same reweighing as in demo01 but histograms are filled (\(p_\ell~\) vs \(Q^2\), in 6-by-5 bins, separately for \(D\) and \(D^*\)), including weight-squared uncertainties, and saved instead |
| demo04 | read the output of demo04 and prints perform the same reweighing to new physics as demo02, printing the histogram bin values – weight, number of events, and weight-squared uncertainty – instead |
| demo05 | read MC events, reweighs \(B\rightarrow (D^*\rightarrow D\pi) \tau\nu\), \(B\rightarrow D \tau \nu\), \(B\rightarrow (D^*\rightarrow D\pi) \ell~\nu\) and \(B\rightarrow D \ell~ \nu\) starting from pure phase space events. Prints total sum of weights reweighing decays with a \(\tau\) to \(S_{qLlL} = x i\), \(T_{qLlL}= x/4\) those with a \(\mu\) to \(S_{qLlL} = -x i\), \(T_{qLlL}= -x/4\) for \(x=0, 0.2, \ldots, 1.0\) |
| demo07 | read MC events, reweighs \(B \rightarrow D \ell~ \nu\) from ISGW2 to BGL with FF variations and fill histograms (\(Q^2\) in 12 bins and \(p_\ell~\) vs \(Q^2\) in 8-by-7 bins), including weight-squared uncertainties |
| demo08 | read the output of demo07 and reweighs by varying the Form Factors with BGL parameters \(\delta~ a_1=x\) and \(\delta~ a_2=x/3\) with \(x=0.0,0.01,\ldots,0.05\) printing out the histogram bin values for weight, number of events, and weight-squared uncertainty. |
| demo09 | same as demo03, but splits the event sample in two different output files |
| demo10 | same as demo04, but merges the output files produced in demo09 (automatically summing histograms) |
| demo11 | same as demo07, but renames the FF variation directions |
| demo12 | same as demo08, but renames the FF variation directions, processes the results of demo11 |
| demo01root | same as demo01 but using ROOT TTree for storage |
| demo02root | same as demo01 but using ROOT TTree for storage |
| demo03root | same as demo01 but using ROOT TTree for storage and TH2D for histograms |
| demo04root | same as demo01 but using ROOT TTree for storage and TH2D for histograms |
| demo04root2 | another take on demo04root |
| demo01card | same as demo01 but using a card file to set the run options |
| demo04mma | same as demo04 but with Wilson Coefficient values passed from the command line (to be called from Mathematica) |
| demo08mma | same as demo08 but with Wilson Coefficient values passed from the command line (to be called from Mathematica) |
| demo04parallel | same as demo04 but using multi-threading |
| demo03.py | python version of demo03 |
| demo04.py | python version of demo04 |
Hammer has been developed by:
Current contributors can be found here.
Hammer is licensed under version 3 of the GPL. Please note the MCnet academic guidelines.
Hammer uses CMake to find Boost. In rare cases, depending on the CMake and boost versions this error may appear: “Imported targets not available for Boost version …”. This is due to a mismatch between the CMake and boost versions (CMake FindBoost has hardcoded the boost library versions existing at the time that CMake version was released) and can be easily resolved by setting the variable Boost_ADDITIONAL_VERSIONS at configure time with the correct Boost version or switching to a more recent CMake version.↩︎